Reel-to-reel magnetic tapes and one-half inch and one-quarter inch magnetic tape data cartridges are commonly used for the storage of electronic data signals. A typical tape data cartridge comprises a metal base plate with pins extending upwardly from the plate to support corner rollers, reel hubs, a drive roller, and posts which extend upwardly to support tape guides. Typically, the walls and top of the cartridge are made of polymeric material and the top usually includes a spring to limit the vertical movement of the reel hubs. The tape alignment must be precise for the recording or the retrieving of the desired data signals on the tape. Therefore, it is very important that the pins and posts maintain their alignment during cartridge use.
With the metal base plate currently used, the pins are rigidly secured to the metal base plate and the metal base plate provides sufficient rigidity to support the various components received on the pins such that the tape does not become misaligned or dislodged during use. However, the metal base plate is a major contributing expense to the overall cost of the cartridge. The use of a polymeric material for the base plate typically does not achieve the equivalent structural strength required for successful use of the cartridge. If such polymeric material is too hard, inserting the pins into the material presents an additional problem of stress and fatigue cracks commonly occuring where the pins are inserted. Conversely, too soft a polymeric material imparts an elasticity to the pins received in the material which results in misalignment of the tape and associated components in use.